After the Domain and Adoption Ceremonies and after the three fates disappear from Olympus.
Zeus says "Everyone sit down... (the Olympians sit down on their thrones)... now that the youngsters have their domains I have some rules to put in place with our new additions. First rule, once they turn 5 they must start spending May, June and July at Camp Half-Blood. Second, since one of their mothers is a hunter of Artemis each child must be with the Hunt for January, February and March each year. The other mother may visit the Hunt as often as they want but must do what the Hunt is doing at that time. Third, Selene, Rhea and Pasiphae must spend August, and September on Olympus with the parent that is an Olympian. While Ariel must spend those months at Atlantis with Amphritrite. While Nyx must spend those months with Persephone in the Underworld.
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Now I believe children that your mothers' have gifts for you.